[PATCH v3 3/4] lib: add "on"/"off" support to kstrtobool

[Kees Cook <keescook@chromium.org>]

Add support for "on" and "off" when converting to boolean.

Signed-off-by: Kees Cook <keescook@chromium.org>
---
v3:
- add dropped descripion change, andy.shevchenko
---
 lib/kstrtox.c | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/lib/kstrtox.c b/lib/kstrtox.c
index e8ba4a013e82..d8a5cf66c316 100644
--- a/lib/kstrtox.c
+++ b/lib/kstrtox.c
@@ -326,9 +326,9 @@ EXPORT_SYMBOL(kstrtos8);
  * @s: input string
  * @res: result
  *
- * This routine returns 0 iff the first character is one of 'Yy1Nn0'.
- * Otherwise it will return -EINVAL.  Value pointed to by res is
- * updated upon finding a match.
+ * This routine returns 0 iff the first character is one of 'Yy1Nn0', or
+ * [oO][NnFf] for "on" and "off". Otherwise it will return -EINVAL.  Value
+ * pointed to by res is updated upon finding a match.
  */
 int kstrtobool(const char *s, bool *res)
 {
@@ -346,6 +346,20 @@ int kstrtobool(const char *s, bool *res)
 	case '0':
 		*res = false;
 		return 0;
+	case 'o':
+	case 'O':
+		switch (s[1]) {
+		case 'n':
+		case 'N':
+			*res = true;
+			return 0;
+		case 'f':
+		case 'F':
+			*res = false;
+			return 0;
+		default:
+			break;
+		}
 	default:
 		break;
 	}
-- 
2.6.3